Answer
$\dfrac{1}{y^{\frac{1}{8}}}$
Work Step by Step
Use the rule $(a^m)^n= a^{mn}$ to obtain:
$=y^{-\frac{3}{4} \cdot \frac{1}{6}}
\\=y^{-\frac{3(1)}{4(6)}}
\\=y^{-\frac{3}{24}}
\\=y^{-\frac{1}{8}}$
Use the rule $a^{-m} = \dfrac{1}{a^m}$ to obtain:
$=\dfrac{1}{y^{\frac{1}{8}}}$
